SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aa954dc7faed6fb04b33d62c276f0fd455c7d220f80456ed6fa1daac974b29e2' 
  AND token = 'dV2Whz6StQZomY4Swc12+Q8H3CgGIjumYC7pQ0jGJiA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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