SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '3434c2efde70cb2f0c09b1f163471d9617eee6ebeb3e7f5cb5896f150e979fac' 
  AND token = 'pbFKyX7Mbp1ukYEIPUjN8niK0AhOaMzcy8Q5qadVEaE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}