SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c98a69faf601515e30ee683b2866ad0b5711287706c230a328bcd7ae222fe1e9' 
  AND token = 'nVSB2j5QK+kGIj1kDeSDU4exLrE2Sb5BKdAGexv/U0E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}