SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2bec009d5bc77f539188f0f53753c0427699c2f56b230fb6f8c6bb5567c7c7d5' 
  AND token = 'lAK7RZ56x/SSVzqpqErUfgwgt+f2vq6A4Xibkm3EYjs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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