SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cc30a2162ed42927fb833e2797e60033590d57ffcae88c70a2b152ee91b51e25' 
  AND token = 'Y+kwnaiQEKG9zWhzp47OTHvqNEqwSRxtugaqUQMxv5g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}