SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '4ce7bd9fb6ff6d959425d52e0c9beb9c9942e262bf255e989bb15e06fd0fbda8' 
  AND token = 'IUUm3j2lFvnfiyYFZHsXei5KSW3ZHgwPFqfdpPcSKU0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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