SELECT 
  1 
FROM 
  cscart_june_setuplock_keys 
WHERE 
  key_id = '10cf342c828c9171b0a5fd60aad366815374298905e0c26dd238b2f03f964f98' 
  AND token = 'EG7m+9u11BVcc0qd+NPFMXR2kA7MeMhKisnGDKhF0I4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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