SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ffa13eaf0c7ab89e8867a064e5b576c11e69f28e8e82ea8869bb1b12c42d7bf4' 
  AND token = '7Zr3CxczI6Dh52m5ZxZWrQDgFnQbzY8aifwBJvOcRSA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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