SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '79d26053acfeb9d105aa5faf28eac66b2ae5eaf663a32c4996cd3125fc2669e9' 
  AND token = 'EsC4wLiHwPqwW439352fYJy8nMdshRPGt6NP4s1PFMI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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