SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4ada342926d17fa04afd3051956444f1783d71bd79483cd97a98b2a0b3bc1ea7' 
  AND token = 'VjCBYABTVDIePVyFCr1ss5fWHyBYR6BryL0yAoS6qm0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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