SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ce99e05451477c2bb9d2f90e46bb51b09d71cc6246df4728ac8dca5b0ae9727b' 
  AND token = 'T3hd1D2KsOAgzGwqs/FOUalKSQjyA+pnOAGL2K+qFLE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00063

JSON explain

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