SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '95bcca742b44f36524a640d9126ffbadbfabcafe6fac2b674112199e72e8ed79' 
  AND token = 'JTDxqcl4RwrKGwKhwISUDHQbqIH0pt+UVdydy0pMKSg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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