SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'f965d15caee169f195e668b14b6fd5b23b506db5a5ff036f472395829bab2b53' 
  AND token = 'UecKJg+OtqTpB/dsGoZnyytNvRR1VECv0GnUc1l1zvs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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