SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '77abcc8ec1da57237d5cdfee3151546877fbb1cf92673e2765ecde83c55b92db' 
  AND token = 'wHMm5i5di8d6TAYNnkCcIyHMQvvNtaw18LmAMwrSn+4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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