SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '071043f0aa2610e8170af8ee51951578a2f03875b576c6b04ce65466533f1741' 
  AND token = 'uBp8+HPb8oAMQYlR+YFUIjUx1QXnIggqhPZS/9lhhRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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