SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '554de797b97b10f703ca4264c0e472fce242c6f3a01ec0b67bd355d47d822ff2' 
  AND token = 'jdPqoCBXnUbJ/qhUZBuQfZMHBhnp0qH0ffq3i+hv3EY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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