SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '54b566534f1ee0129684647ffd4111d0e67db64c7f15c353c418e7913493b410' 
  AND token = 'Pp9rN8bKXj1dP6qMJ4hvzWDPr1yU8pV/y4cPPy0uyNg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00018

JSON explain

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