SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd22ce47fb278db141c286438a70415ee4ededf36192c7b28fef1415aa8814e25' 
  AND token = 'u1FMB3Zzc1EWTKH9QIUSbEOre1QE/hSzjMrft+nc/hI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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