SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '2440e3c1da8c358452f5cf7c15652bd7db4df71c58aeb0dd969878c88e06f8a5' 
  AND token = 'gw5+rIblZIgDLuE/6KV7kkRBKXNhHvUsBnniHrjymJA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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