SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2905fd1316c5df560d4de681cc469851b0e476e089752b0bfff9ec8111a596e9' 
  AND token = 'T3+BVaPYQLlzlzRn/V8dUW53h3+Vb8GWVSm0H6+vn1E=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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