SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd152e7a0d919b36aa8c18b10711af0b509d48120a756e33cc528ad1431c73134' 
  AND token = 'iF1khYEMVs89QYQieGDOws4l9oWh0fIY6FDh7IYls5w=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

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