SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5dbacb5144ab59e92cfd84400b92fa307cc823689de4d19227400468b1962745' 
  AND token = 'T9gAfhM5uNX0jVWbXCnc45F3oWc2lL/qNLJyuohFTVQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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