SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6454b58a53c2a960aa47ecd323c9a242203128a3be93013b89f985b5145f88a9' 
  AND token = 'r0qYoMsqNhvqz1u2ff/cOTlgEnm9R+4VqeiSVaDJ1d0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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