SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bb8d38d9bc19247ad421b8aebb19c257c757d780b2ac5a188f50f434914b52bc' 
  AND token = '1Vz7MkIA4j7arCitOTe270gp1RdfhcmjOxeRTnjEhCs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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