SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0d85904f73737bd9e47807a33c4cd34cfc3131f2f66c5bca82e14c7e4eebce7b' 
  AND token = '0a020guq2aFHuyiaxoG6jBtConEShrTQ0rGStTZMoDE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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