SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'df58b8af9246eb722c3fabb6bc636fef66c492da60a47deaaf093c71b644aba6' 
  AND token = 'Pey+KK5UYiyF1rOaleTG7ammjH9rfkETUb0TwShys80=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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