SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '58a2a02d809d132a42196b4dccc2d95c7a8cf1155b7a6f251662a1c4f743bac9' 
  AND token = 'I4odPlvH/WkHiLXkWe10OVFL94A9Ap2quuH97vT5uoE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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