SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '33778ac5bda6a04cf83d36897c9c604ea76a5e127bdb7b8c17335a2d30471651' 
  AND token = 'l2Wzo2J/mDfplsN1+r+iWPlZenb2rOgKidKOuuAhpRE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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