SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'fb75c5e897ce77c2059ba56ef11857d79686f44e29b9f17462d393d224e9878c' 
  AND token = 'H5K4CaoE/0uAgbg/tPzaYShaVSPEFEvOFqIXfqrf558=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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