SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'cb0e57a571ba99cf1725375686fa2be9e7e7ae874bea8c86158b013a819a0e65' 
  AND token = 'jHfglXS3mPEjvBwK6eKvkZwDyg9Sr+q3V5OMt/FPJ8g=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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