SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b3c99341b8a61a760098cdede1c4c04911ce839b0bd7eac17c6fc9592567e9ac' 
  AND token = 'oM/XYA8XC6Sge030YQA+fcaPY5w3Q+ubgzKGWVbzcHs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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