SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '5c79d94f253eeb9936501d1b66c5f8042f935d1618378df54982490d9f651b39' 
  AND token = 'ciR6cj1NP2OzVsSLzoX6h/LmzO2H/RvA+008mGBOu1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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