SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7113670973b2b64679f582476e749d9c2f8c50e2e0f565fdcf5f37f337675636' 
  AND token = 'iWKA0ATuhjbfvP2vXYjBHVMtfnANPoqc6GgRQWJHXnY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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