SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e41af837cfe741611eb7a4fac5bd7cf3e22abbafc9b1dcf20a5340c74fc2a45c' 
  AND token = '2Mxutn1KhDoCLAJwY55/Z5zgcLj+LmQwYVP78g1QZ+A=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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