SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2dfeda845d4d10fb02a550a77d1b9b0f618e0761a6a0a7210947665d42f091ba' 
  AND token = 'IXCdAhfz6suz/1/191E4gmnmJ0gECKN0Sty7LvD6R+I=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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