SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f7bad93bc44cb36dbb232fe3d9c5ba62aa822dcd3a7a69c8b2fefd58fafcfea0' 
  AND token = '3jctYMIQVlVrjr0x0vvU8YCkHBlLOnLrzOwQqgnz2MM=' 
  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"
    }
  }
}