SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '709058c1678aa4322323589db513979458808e0a21239c149854f74dc1f255e1' 
  AND token = 'eqoN5RWJ0mLVyH5WBZL84AwdXJ9TWbxU+jrX1aoNptE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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