SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3c8227d75772284ec1178aa2c97f6b85767ffb7854864eb58fa616c162e85d79' 
  AND token = 'bQinMqjUaOkshTvIL6YqnkSAU51e+jq0w1C32oJWGFY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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